Electric heater



Oct. 30,1923. 1,472,171

J. 0. HAYNSWORTH ELECTRIC HEATER Filed May 14 1921 WITNESSES: INVENTOR jffi Jul/us D. Haynsworfh ATTORNEY Patented Oct. 30, 1923.

UNITED STATES 1,472,171 PATENT OFFICE.

JULIUS D. HAYNSXVORTH, 0F MANSFIELD, OHIO, ASSIGNOR 'IO WESTINGHOUSE ELEC- TRIG PRODUCTS COMPANY, A CORPORATION 013 MICHIGAN.

ELECTRIC HEATER.

Application filed May 14,

To all whom it may concern.

Be it known that I, JULiUs D. HAYNs- WORTH, a citizen of the United States, and a resident of Mansfield, in the county of I Richland and State of Ohio, have invented a new and useful Improvement in Electric Heaters, of which the following is a specification.

My invention relates to electrically heated apparatus and particularly to electric heaters and it has for its object to provide a relatively simple, compact and rugged electrio heater which may be used in rooms or spaces filled with an explosive or inflammablc mixture.

In practising my invention, I provide an electric-resistance element which is mounted in a perforated casing, with awire screen of relatively fine mesh located inside of said I0 casing and surrounding said heating element, to prevent the travel of any inflammable mixture which has been ignited by the heated resistance element beyond the wire screen. i

The device disclosed in the present application is an improvement on that disclosed in Serial No. 348,896. filed Dec. 10, 1919, by

F. Thornton, in, and assigned to the Westinghouse Electric Products Company.

Referring to the single sheet of drawings,

Figure l is a view in front elevation, cer tain parts being broken away, and

Fig. 2 is a view, in vertical cross-section, on the line II-II of Fig. 1.

A heating element, indicated generally by 1, comprises a perforated metal casing 2 of substantially tubular shape, the overlapping ends of which may be welded or brazed together in a manner well known in the art. One end of the tubular member 2 is provided with a head 3 in which is located an opening 4, a threaded metal sleeve 5 being located adjacent the head 3 and the opening i and suitably secured to the head 3 by spinning over the metal, or by soldering. At the other end of the member 2, I provide an impertorate head 6, which may have a down-turned flange portion 6 within which the end of the-member 2 may be located, the two members being suitably secured together.

The heating means comprises a refractory terminal block 7, suitably cored to receive two contact terminals 7 adapted to cooperate With a suitable plug member (not 1921. Serial No. 469,441.

shown) for connection to a supply circuit, in the usual manner. Located ad acent to the member 7 15 a spacing member 8 which is adapted to co-operate with a tubular reiractory member 9 on which a resistor wire 10 is wound. An end member 11 is located at the other end of the tubular member 9, both the members 8 and 11 being provided with a reduced portion 12 adapted to interfit with the member 9 to maintain them substantially coaxial.

In order to maintain the members 7, 8, 9 and 11 in proper operative relation, I pro-- vide a threaded bolt 13, at one end of which a nut 1 1 is located in a cored out portion of the member 7. A nut 15 is screwed on the rod 13 to engage the member 11 and thus press the members 7 .8, 9 and 11 together, substantially in the position indicated in the drawing.

In order to hold one end of the heating means in the casing, I provide a suitable metallic casing 16 which engages a shoulder portion of the member 7 and projects sufiiciently beyond the contact terminals 7 to substantially surround them. A threaded metallic sleeve member 17, having an inturned flange portion 18, is provided, the internal diameter of the flange portion 18 being such as to permit of the placing of the member 17 over the casing 16 and of then so turning it as to cause it to take the position indicated in Fig. 2 to securely hold the member 7. The other end of the resistor means is held in its proper operative position in the casing 2 by the other end. of the bolt 13, which projects through a suitable opening 19 substantially in the center of the head 6, being clamped thereto by means of a plurality of nuts 20.

A hook member 21 is suitably secured to the casing 2 to permit of hanging the heating element upon a suitable support if desired. i

If this type of heater is used to maintain the temperature of a radiator of an auto mobile substantially above the freezing point, by being energized while located under the hood of the car, it is possible that gasoline vapors may be generated which may be ignited when the temperature of the resistor 10 becomes relatively high.

, In order to prevent this action, I provide a wire screen 22 of relatively fine mesh located inside of the casing 2 and surrounding the resistor. l 1 members 23 at the en permit of clzrmpii or .1

to the casing the menmers hciny riveted together.

The finction oi? the device emib-oihgi'ng my invention, will be understood to c iznsist prinnuril in preventing the passage of an flame that may result from the Contact o:

small quantities oi infimnn'nrlile vepo, h, which may find their way through the cusing 2 and the screen 9:2 will the resistor 10 when heated to such 2!, temperature as will cause to glow.

However l hm" found enoth upplioe.- (11011 for it heater oi? the type dew-mined. above" particularly iii rooms or enclose-(l spaces in whieh :1 (lust may be liber: ted which hecomes explosive when combined with air in certain proportions or even in rooms in which dry 'XPlOSl'VQS ore lrinillei or s ored It is not necessary, in the letter that the temlwre iii'e of the lmiting OlOl'llPE'll) he so high as to call so it to glow as necesuary in the use of: explosive vapors, 2%; such explosive mixtures may become ignited be exploded by an open resistor eleinen which is a temperature below that which would cause it to glow.

i. he

use of the device embodying my in- 'ention effectively prevents the spread of the burning vapor and prolmhly prevents the explosive mixtures or dust from getting into direct contact with the exposed re slor, henc my device provides :1 male heating eleinei Which may he used Where explosive llllRblllQS of any kind are present.

Various modifimtions may he inml in the device enllio i i'ing my invention Without departing from the spirit and scope thereof rid I desire that only such limitr ions shell he placed lhereoi'l 21s are limited by the prior art or are specirefill set forth in the eppcnded clui in.

I claim my invention:

An electric heating; means i'or use in (X-- plosive-vepor-iilled rooms con'iprising :1 resistor member adapted to he heated suhstantially to izicendescence, 2t perforated cylindrical eusing surrounding said resistor 21 ember; imperforete heads secured to said (VlilHlI'lCZll casing, and a. substantially tubuliir line-mesh semen inside ol said casing and having its ends secured thereto.

in testimony whereof I have hereunto subscribed. my name this 11 day of hiley, 1921.

JULEUS D. HAYNSWOPTH. 

